{
  "bibcode": "2009GCN..9580....1M",
  "body": "J. Mao, R. Margutti (INAF-OAB) and C. Guidorzi (U. Ferrara) report\non behalf of the Swift-XRT team:\n\nWe have analyzed the first three orbit data (6.9 ks exposure) of the\nSwift ToO observation of the INTEGRAL burst GRB 090625B (Gotz, GCN\nCirc. 9572).\n\nSwift-XRT observations started at 14:30:13 UT (Mao et al. GCN Circ. 9573),\n4ks from trigger.\n\nThe source is fading with a best fit simple power law model index\nof alpha= 0.6+/- 0.3, confirming its nature of X-ray afterglow.\n\nA spectrum extracted from PC mode data can be modelled with an\nabsorbed power-law, with Gamma = 3.3 +1.1/-0.8 and NH = (3.7\n+2.2/-1.7)x1021 cm^-2. The Galactic column in this direction is\n2.1 x 1020 cm-2 (Kalberla et al. 2005).\n\nThe counts to observed (unabsorbed) 0.3-10 keV flux conversion factor\ndeduced from this spectrum is 2.8 x 10-11 (1.8 x 10-10) erg cm-2 count-1.\n\nIf the light curve continues to decay with a power-law decay index of 0.6,\nthe count rate at T+24 hours will be 6.3x10-3 count s-1, corresponding to\nan observed (unabsorbed) 0.3-10 keV flux of 1.8x10-13 (1.1x10-12) erg \ncm-2 s-1.\n\nThis circular is an official product of the Swift-XRT team.\n\n[GCN OPS NOTE(26jun09): Per author's request, \"Cristiano\" was replaced\nwith \"Guidorzi\".]",
  "circularId": 9580,
  "createdOn": 1246016650000,
  "email": "jirong.mao@brera.inaf.it",
  "subject": "GRB 090625B: Swift-XRT refined analysis",
  "submitter": "Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>",
  "eventId": "GRB 090625B"
}